Actress Tia Mowry announced on Instagram earlier this month that she’s carrying her second child, and last week she posted an image of herself from a photo shoot when she was just one month along. In the caption, Mowry giddily explained what clued her in to her pregnancy: The photographer had a dog who paid her a lot of attention—and that made her wonder if the dog sensed something she wasn’t able to yet.
Mowry isn’t the only expectant mom who noticed a pooch acting more clingy and cuddly; other women have also said that their dogs behaved differently when they were pregnant too. Science hasn’t weighed in definitively as to whether canines have a sixth sense about human pregnancy. So we reached out to dog experts to find out if your pooch really can tell you’ve got a bun in the oven.
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Jeff Werber, PhD, president and chief veterinarian of the Century Veterinary Group in Los Angeles, credits dogs’ keen sense of smell for their ability to sense physical and emotional changes in humans.
“We have 5 million receptors in our noses, dogs have 200 million,” Dr. Werber tells Health. “Dogs can detect when a seizure is coming on, when a person is hypoglycemic, and they can detect cancer and fear, so there’s certainly scents they can pick up on.”
But what about human pregnancy?
Dr. Werber believes dogs can also smell the hormonal changes going on in a woman’s body at that time. Canines may not understand that this new scent of your skin and breath is caused by a developing baby, but they will know that something is different with you—which might cause them to be more curious or attentive.
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It’s not just your scent that gets your dog’s attention during pregnancy; hormone-driven mood swings may also have an influence on your furry family member. “Some dogs can be very sensitive to people’s moods, and they will respond if they know their owner is upset or angry, ” Peter L. Borchelt, PhD, a New York–based certified animal behaviorist, tells Health. If they sense that you are more emotional or anxious than usual—as many women are at some point during pregnancy—they are more likely to stay close and seek more attention from you, Borchelt says.
Dogs might also be reacting to a change in your daily routine. For example, you’re getting up in the middle of night to pee, or you’re staying home more due to morning sickness. These habit changes can leave them curious and confused. Borchelt explains it like this: “If they were people, they would say, ‘Gee what’s going on, something’s different here but I’m not sure what nor why.””
And though Borchelt says this is hard to scientifically prove, if your four-legged BFF sits on your lap or nuzzles up to your chest for petting, they might be able to hear the infant’s heartbeat. That lets them know something’s up—and they become protective or start to compete for your attention.